论文标题
视频压缩应用的时空自适应量化
Spatiotemporal Adaptive Quantization for Video Compression Applications
论文作者
论文摘要
JCT-VC HEVC HM 16包括一个名为AdaptiveQP的编码单元（CU）级别自适应量化参数（QP）技术。它旨在仅根据LUMA CB中样品的方差来感知地调整Y，CB和CR编码块（CB）中的QP。在本文中，我们提出了一种由两种贡献组成的自适应定量技术。第一个贡献涉及在Cu中除LUMA样品外的Chroma样品方差。第二个贡献涉及CU时间信息以及CU空间信息有关。此外，我们将lambda精制的QP技术集成到我们的方法中，以降低复杂性与速率失真优化过程中的多个QP优化相关联。我们在4：4：4、4：4：2：2：2：2：0和4：0：0：0 YCBCR测试序列上评估了提出的技术，为此我们使用Bjontegaard Delta速率（BD率）度量量化了结果。我们的方法可实现23.1％（Y），26.7％（CR）和25.2％（CB）的最大BD率降低。此外，达到了最大编码时间缩短4.4％。
JCT-VC HEVC HM 16 includes a Coding Unit (CU) level adaptive Quantization Parameter (QP) technique named AdaptiveQP. It is designed to perceptually adjust the QP in Y, Cb and Cr Coding Blocks (CBs) based only on the variance of samples in a luma CB. In this paper, we propose an adaptive quantisation technique that consists of two contributions. The first contribution relates to accounting for the variance of chroma samples, in addition to luma samples, in a CU. The second contribution relates to accounting for CU temporal information as well as CU spatial information. Moreover, we integrate into our method a lambda refined QP technique to reduce complexity associated multiple QP optimizations in the Rate Distortion Optimization process. We evaluate the proposed technique on 4:4:4, 4:2:2, 4:2:0 and 4:0:0 YCbCr test sequences, for which we quantify the results using the Bjontegaard Delta Rate (BD-Rate) metric. Our method achieves a maximum BD-Rate reduction of 23.1% (Y), 26.7% (Cr) and 25.2% (Cb). Furthermore, a maximum encoding time reduction of 4.4% is achieved.
